Project description:Cardiovascular disease is the major cause of mortality in breast cancer survivors. Chemotherapy contributes to this risk. Accordingly, we aimed to define the mechanisms of long-term vascular dysfunction caused by neoadjuvant chemotherapy (NACT) and identify novel targets for pharmacological intervention. We studied human mammary arteries from women who had undergone NACT for breast cancer using docetaxel, doxorubicin and cyclophosphamide and women with no history of such treatment matched for key clinical parameters. Mechanisms were further explored in wild-type and Nox4-/- mice and human microvascular endothelial cells. Endothelium-dependent relaxation was severely impaired in patients after NACT, while endothelium-independent responses remain normal. This was mimicked by 24-hour exposure of arteries to NACT agents ex vivo. When applied individually, only docetaxel significantly impaired endothelial function in human vessels.
Project description:Hypertension is a common cardiovascular disease that is related to genetic and environmental factors, but its mechanisms remain unclear. DNA methylation, a classical epigenetic modification, not only regulates gene expression but is also susceptible to environmental factors, linking environmental factors to genetic modification. Therefore, globally screening differential genomic DNA methylation in hypertensive patients is important for investigating novel hypertension mechanisms.Differential genomic DNA methylation in hypertensive, prehypertensive, and healthy control individuals was screened using the Illumina 450K BeadChip and verified by pyrosequencing. Plasma oviduct glycoprotein 1 (OVGP1) levels were determined using an enzyme-linked immunosorbent assay. Ovgp1 transgenic and knockout mice were generated to analyze the function of OVGP1. The blood pressure levels of the mouse models were measured using the tail-cuff system and radiotelemetry methods. The role of OVGP1 in vascular remodeling was determined by vascular relaxation studies. Protein–protein interactions were investigated using a pull-down/mass spectrometry assay and verified with coimmunoprecipitation and pull-down assays. We found a hypomethylated site at cg20823859 in the promoter region of OVGP1, and the plasma OVGP1 levels were significantly increased in hypertensive patients. This finding indicates that OVGP1 is associated with hypertension. In Ovgp1 transgenic mice, OVGP1 overexpression caused an increase in blood pressure, dysfunctional vasoconstriction and vasodilatation, remodeling of arterial walls, and increased vascular superoxide stress and inflammation, and these phenomena were exacerbated by angiotensin II infusion. In contrast, Ovgp1 deficiency attenuated angiotensin II-induced vascular oxidase stress, inflammation, and collagen deposition. These findings indicate that OVGP1 is a prohypertensive factor that directly promotes vascular remodeling. Pull-down and coimmunoprecipitation assays showed that myosin heavy chain II-A (MYH9) interacted with OVGP1, whereas inhibition of MYH9 attenuated OVGP1-induced hypertension and vascular remodeling. CONCLUSIONS: Hypomethylation at cg20823859 in the promoter region of OVGP1 is associated with hypertension and induces upregulation of OVGP1. The interaction between OVGP1 and MYH9 contributes to vascular remodeling and dysfunction. Therefore, OVGP1 is a prohypertensive factor that promotes vascular remodeling by binding with MYH9.
Project description:Hypoxia can induce vasoconstriction followed by vascular remodeling including hypertrophy and hyperplasia of pulmonary vascular smooth muscle and proliferation of endothelial cells. The goal of this project is to elucidate the genes involved in vascular remodeling following pulmonary hypertension. Total RNA was isolated from lungs of normoxic and hypoxic treated animals. Keywords: other
Project description:<p>Arterial stiffening is a hallmark of early vascular aging (EVA) syndrome and an independent predictor of cardiovascular morbidity and mortality. In this case-control study we sought to identify plasma metabolites associated with EVA syndrome in the setting of hypertension. An untargeted metabolomic approach was used to identify plasma metabolites in an age-, BMI- and sex-matched groups of EVA (n = 79) and non-EVA (n = 73) individuals with hypertension. After raw data processing and filtration, 497 putative compounds were characterized, out of which 4 were identified as lysophosphaditylcholines (LPCs) [LPC (18:2), LPC (16:0), LPC (18:0) and LPC (18:1)]. A main finding of this study shows that identified LPCs were independently associated with EVA status. Although LPCs have been shown previously to be positively associated with inflammation and atherosclerosis, we observed that hypertensive individuals characterized by 4 down-regulated LPCs had 3.8 times higher risk of EVA compared to those with higher LPC levels (OR = 3.8, 95% CI 1.7 – 8.5, P < .001). Our results provide new insights into a metabolomic phenotype of vascular aging and warrants further investigation of negative association of LPCs with EVA status. This study suggests that LPCs are potential candidates to be considered for further evaluation and validation as predictors of EVA in patients with hypertension </p>
Project description:Endoglin is a membrane glycoprotein primarily expressed by the vascular endothelium and involved in cardiovascular diseases. Upon the proteolytic processing of the membrane-bound protein, a circulating form of endoglin (soluble endoglin, sEng) can be released, and high levels of sEng have been observed in several endothelial-related pathological conditions, where it appears to contribute to endothelial dysfunction. Preeclampsia is a multisystem disorder of high prevalence in pregnant women characterized by the onset of high blood pressure and often associated with increased levels of sEng. Although a pathogenic role for sEng involving hypertension has been reported in several animal models of preeclampsia, the exact molecular mechanisms implicated remain to be identified. To search for sEng-induced mediators, we have analyzed the protein secretome of human endothelial cells in the presence of sEng. We find that sEng induces the expression of BMP4 in endothelial cells, as evidenced by their proteomic signature, gene transcript levels and BMP4 promoter activity. A mouse model of preeclampsia with high sEng plasma levels (sEng+) showed increased levels of BMP4 transcripts in lungs and increased circulating BMP4, compared to those of control animals. In addition, after crossing female wild type with male sEng+ mice, hypertension appears 18 days after mating, precisely coinciding with the appearance of high plasma levels of BMP4. Also, serum levels of sEng and BMP4 are positively correlated in pregnant women with and without preeclampsia. Interestingly, sEng-induced arterial pressure elevation in sEng+ mice was abolished in the presence of the BMP4 inhibitor noggin, suggesting that BMP4 is a downstream mediator of sEng. These results provide a better understanding on the role of sEng in the pathobiology of preeclampsia and other cardiovascular diseases, where sEng levels are increased.
Project description:Hypoxia can induce vasoconstriction followed by vascular remodeling including hypertrophy and hyperplasia of pulmonary vascular smooth muscle and proliferation of endothelial cells. The goal of this project is to elucidate the genes involved in vascular remodeling following pulmonary hypertension. Total RNA was isolated from lungs of normoxic and hypoxic treated animals.
Project description:6 timepoints: Day 0 (normal controls), progressively developing neointimal vascular proliferation and pulmonary hypertension in vehicle treated animals (Days 14, 21, 28 and 35) and triptolide-treated animals at Day 35. Replicates: 6 for Day 0 (normal) 2 for Daty 14 3 each for Days 21, 28, 35 and Triptolide -treated at day 35 (T)
Project description:Despite its high prevalence and economic burden, the etiology of human hypertension remains incompletely understood. Here we identify the transcription factor Gata5, as a new gene involved in regulation of blood pressure (BP). GATA5 is expressed in microvascular endothelial cells (mEC) and its genetic inactivation in mice leads to hypertension, vascular endothelial dysfunction and renal inflammation. Aged Gata5-Null mice develop salt-sensitivity and target-organ damage reminiscent of the progression of human hypertension. Endothelial-specific inactivation of Gata5 increases BP and leads to vascular endothelial dysfunction, confirming the endothelial component of Gata5 inactivation-related hypertension. To directly assess the effect of loss of GATA5 on endothelial cells, we generated a stable GATA5 knockdown cell line (HDMEC-Gata5KO) by infecting human dermal microvascular endothelial cells with a lentiviral vector containing an anti-Gata5 shRNA followed by a transcriptomic analysis. The control cells were infected with a lentivirus containing an empty vector pLKO2.